Biomedical subjects

J A Ahovuo

Publications and source records attributed to J A Ahovuo.

3 recordsLinked to original sources

PubMed2004

Bone stress injuries.

Bone stress injuries are due to cyclical overuse of the bone. They are relatively common in athletes and military recruits but also among otherwise healthy people who have recently started new or intensive physical activity. Diagnosis of bone stress injuries is based on the patient's history of increased physical activity and on imaging findings. The general symptom of a bone stress injury is stress-related pain. Bone stress injuries are difficult to diagnose based only on a clinical examination because the clinical symptoms may vary depending on the phase of the pathophysiological spectrum in the bone stress injury. Imaging studies are needed to ensure an early and exact diagnosis, because if the diagnosis is not delayed most bone stress injuries heal well without complications.

Athletic Injuries↗

PubMed2002

MR imaging, bone scintigraphy, and radiography in bone stress injuries of the pelvis and the lower extremity.

PURPOSE: To compare MR imaging, radiography and bone scintigraphy in the diagnosis of stress injuries to bones of the pelvis and lower extremity. MATERIAL AND METHODS: Fifty consecutive conscripts with clinical signs of a stress injury to bone underwent MR imaging and bone scintigraphy. Forty-three patients also had radiographs available. Bone scintigraphy served as a gold standard. RESULTS: Compared to the bone scintigraphy, the sensitivity of radiography was 56%, specificity 94%, accuracy 67%, positive predictive value (PPV) 95%, and negative predictive value (NPV) 48%. The kappa value for radiography and bone scintigraphy was fair (0.39). Correspondingly, the sensitivity of MR imaging was 100%, specificity 86%, accuracy 95%, PPV 93% and NPV 100%. The kappa value for MR imaging and bone scintigraphy was very good (0.89). MR imaging depicted 3 bone stress injuries that were not visible on bone scintigraphy. Positive findings obtained from radiography correlated with MR signs of fracture line or callus (p<0.001). CONCLUSION: MR imaging is more sensitive than two-phase bone scintigraphy, and MR imaging should be used as the gold standard in the assessment of stress injuries of bone. Radiography reveals mainly the late phases of bone stress injuries, such as stress fracture and callus.

Adult↗

PubMed2001

Dynamic contrast-enhanced MR imaging in symptomatic bone stress of the pelvis and the lower extremity.

PURPOSE: To assess the value of dynamic contrast-enhanced MR imaging in bone stress of the pelvis and the lower extremity. MATERIAL AND METHODS: Thirty patients (37 reactions; aged 17-25 years, mean 20.5 years) with MR findings of 37 bone stress reactions were examined using dynamic gadolinium contrast enhancement. The enhancement was evaluated with time-intensity curves. The highest slope and maximum enhancement values were calculated and compared with the different precontrast MR imaging signs of bone stress reactions. RESULTS: There was a significant difference in the highest slope values between the site of the bone stress reaction and the reference points. In 24 of the 37 reactions the dynamic contrast enhancement was regarded as positive. A fracture line, callus, and muscle edema were the MR imaging signs which had a significant correlation to the dynamic contrast enhancement. Neither periosteal nor marrow changes showed any significant correlation. A new MR grading system for bone stress reactions could be assessed. CONCLUSION: Increased tissue perfusion could be seen if precontrast MR imaging revealed callus, fracture line or muscle edema surrounding the bone stress reaction.

Adolescent↗